Then, of course, you need to eventually compile the order for your prototype. I had no idea that SMD diodes, for instance, don't use the same footprint codes as SMD LEDs (light-emitting diodes). Who'd a thunk the light-emitting part made a difference? You must check these things very carefully when compiling your order.
For the SMD-impaired, like myself, here are some good pages discussing the mysterious world of packaging in that teensy world:
Then there's that voice in the back of your head: Aren't there some other parts you might need for other projects? Better order them too while you're at it. Maybe that's the geek equivalent to shoe-shopping. Sigh.